Corona-preventing apparatus



Sept. 4, 1928. 1,683,152

J. BIERMANNS CORONA PREVENTING APPARATUS Filed Feb. 8, 1926 rf/VSULAT/ON 2- Inventor Jose? Biermanns,

His Attorney- Patented Sept. 4, 1928.

UNITED STATES PATENT OFFICE.-

' JosEE 'nmamzms, or mnsnronsr, NEAR BERLIN, GERMANY, ASSIGNOR To GENERAL ELECTRIC COMPANY, AYCORPORATION or NEW. YORK.

My invention relates to apparatus for prevent-ing the formation of corona onconductors subjected to high potential belng particularly applicable to the preventlon of corona formation on step resistances of o l switches and an object of my lnventlon 1s the provision of an improved apparatus for this purpose.

My invention will be better understood from the following description taken 1n connection with the accompanying drawlng, and its scope will be pointed out 1n the appended claims.

.In the single figure of the drawing which represents a resistance and a conta1ner in which the resistance is mounted embodying my invention, 1 represents the resistance which may be in the form of a hehx and may be of wire of such a size that when ra sed to the potential of the circuit with which it is used would normally \be surrounded by a corona discharge. 0 rounded by a tube 2 of insulating mater al having metallic inserts 3 imbedded thereln.

These inserts are completely Insulated from each other by the material of the tube and have overlapping portions. They are shown embedded in the tube at various depths and may be in the form of separaterings or bands.

A convenient method of making the tube 1s by rolling it up ofv paper with a suitable binder and inserting metal foil strlps as the tube is being rolled up. The ends of the tube are shown enclosed bymetal caps 4*wh1ch overlap the ends of the tube and also the end 1nserts. The caps 4' are thereby insulated from the end inserts but are, nevertheless, in electrostatic relation therewith; These end caps preferably make tight connections with the tube to exclude moisture and are glven a rounded contour. The two ends of the resistance are connected respectively to the two end caps 4 and the external circuit may be connected to these caps by suitable connec- .5 tions represented diagrammatically by the leads 5 and 6.

The container thus formedconstitutes a shield for the resistance providing a substantially uniform distributionpf field through- ;0 out its length and in effect 1s equivalent electrostatically to a conductor surrounding the resistance of a size commensurate with the tube. Corona formation on the relatively The resistance 1 is sur- 1 CORONA-PREVENTING AIPPARATUS.

Application filed February 8, 1926, Serial No 86,6?3, and in Germany February 23, 1925.

small wire forming the resistance is thereby avoided and a convenient weather-proof container is thereby provided.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Means for preventing the formation of corona about a resistance conductor comprising a tubular shield of insulating material adapted to receive the conductor, said shield having members closing the ends thereof and having spaced conducting inserts embedded thercinand extending in a series lengthwiseof the tube.

2. Means for preventing the formation of corona about a resistance comprising a tubeof insulating material constructed to receive the resistance, caps closing the ends of the tube and connected respectively to the ends of the resistance, and spaced overlapping con ducting inserts embedded in the tube and extending in a series from one cap to the other.

3. Means for preventing the formation of '75 corona about a resistance coil comprising a hollow tube of insulating material constructed to receive the resistance coil, conducting caps closing the ends of the tube and connected respectively with the ends of the resistance and a plurality of spaced conducting inserts embedded in the wall of the tube and arranged in a series extending from one end of the tube to the other.

4. Means for preventing the formation of 85 corona about a resistance comprising a container therefor of insulating material having embedded therein a series of separated overlapping metallic inserts, and metallic end caps for the container connected res ectively with the ends of the resistance an in electrostatic relation with the endinserts,

5. Means for preventing ,the' formation of corona about a resistance comprising a tubular container therefor constructed of insulat ing material having embedded therein a series of metal foil inserts spaced from and overlapping each other, and a rounded cap at each end of the container, said caps being connected with the respective ends of the resistance and having portions overlapping the inserts adjacent the ends of the tube.

In witness whereof, I. have hereunto set my hand this 15th day'of January, 1926,

JOSEF BIERMLANNS, 

